Morphology of human diploid fibroblasts with different experimental treatments. HDFs at young age, passage 4 (A) and senescent (passage 30) (B). The senescent cells showed increased cytoplasm volume and vacuoles, and loss its original fibroblastic shape by acquiring flattened feature. Cells with H2O2-induced oxidative stress showed similar morphological changes like senescent cells (C). The γ-tocotrienol-treated cells showed similar morphology to young cells (D). Micrographs are shown at ×200 magnification.